I use Audirvana on MacBook Pro. With Mac OS X Audirvana automatically loads a bunch of VST plug-in's. The one I have used is "Apple AUNBandEQ" which is pre-loaded. it has an unlimited number of filters. Or at least, I have not reached the parametric EQ limit.
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You access the Audio Units menu under "Audirvana: Audio Settings" menu. Then, it offers the ability to setup a custom EQ setting. I use REW to discover where my room modes are and usually limit most EQ to that area. But, with speakers like the B&W 606 I tried to address the upper midrange as well. You can create a setting and save it. I have one for the Revel M105, BMR Monitors, cheap $10 Sony MDR-AZ110 headphones and one with a simple elevated bass boost.
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It's easy to switch between settings and decide which one you prefer. I still find myself listening without EQ in many situations. But it's nice to have the feature built into Audirvana when you want it. There is a VST plug for Dirac Live 3 if you happen to own it and a lot of other free to expensive VST EQ choices too. In addition, my RPi4 Moode application has parametric EQ options built in and I have an RPi4 with Moode installed on each stereo setup. If I wanted to leave Audirvana with a flat response and setup the Moode EQ for each speaker configuration that's a free option too. It seems EQ is available from several different sources these days. If you can use REW, you can get a good idea where to apply it.